Wikipedia:Reference desk/Archives/Computing/2010 August 20

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August 20[edit]

Burning FLV straight to DVD[edit]

Hello! I've spent the better part of four hours split between today and yesterday trying to convert a Flash video file into a format that Windows Movie Maker would like so I could burn it to a DVD that would be readable by a standard DVD player. The problem was every time I tried either the Windows Movie Maker couldn't play the converted file, or VLC Player's converter or Mencoder (which use the same set of codecs, as I understand it) mangled the file one way or another. Needless to say, I'm fed up trying to jump from one encoding to another and was wondering if anyone knows a way to burn FLV files to DVD-player-readable DVDs with as little effort as possible. A quick Google search suggests some program called "FlashOnTV," but I'm weary of freeware programs I've never heard of, that they might contain some malicious code or won't do the job right, given the hard time I've had working with completely open-source alternatives. Suggestions? By the way, I'm using DVD+RWs, but I assume that these should work the same as DVD+Rs, with the rewritability as an extra. Much appreciated.--el Aprel (facta-facienda) 05:12, 20 August 2010 (UTC)

I use a shareware tool called ConvertXtoDVD, it's always worked for me. Sandman30s (talk) 08:52, 20 August 2010 (UTC)
For converting flv to something Windows Movie Maker will likely understand you can use avidemux. Load the flv into it, set video option to "MPEG-1", audio to "mp3", and format to "avi", then File -> Save -> Save video, and it will encode it. 1230049-0012394-C (talk) 13:39, 20 August 2010 (UTC)
Aaah, thank you! Avidemux has to be the easiest encoder/decoder I've ever set eyes on. It performed much more reliable conversions than what I was getting with other software. I will have a look at CovertXtoDVD too, which probably saves time without an intermediate format. Thanks for the help.--el Aprel (facta-facienda) 23:05, 20 August 2010 (UTC)


How do I download a Flickr movie? I know how to download a Flickr picture (i.e. jpg). I use Microsoft Vista.--Doug Coldwell talk 12:14, 20 August 2010 (UTC)

VideoDownloadHelper addon for Firefox can download them 1230049-0012394-C (talk) 13:26, 20 August 2010 (UTC)
I don't believe I have Firefox. Do I have to download it first? Will it work on Vista?--Doug Coldwell talk 14:31, 20 August 2010 (UTC)
Yes you will need to. Yes it will. If you are still using IE, FF will make you happy. -- Finlay McWalterTalk 15:02, 20 August 2010 (UTC)
Downloading video from Flickr is (1) difficult, but (2) not impossible. According to Flickr, this is against the rules; users "may embed your video in other web pages, provided they have permission, but can’t “download” them. Flickr uses a weak version of digital rights management by hiding the video data behind a server-side Flash application. For example, this video can be streamed and the complete data is downloaded to your computer, but "stays" inside the Flash framework. You will need a third-party program, like VideoDownloadHelper to intercept the video data as it transits from the Flickr server to your Adobe Flash player in your web-browser (or the straw-man Flash-player that VDH emulates internally). Other programs exist that can perform this function; or if you are a very technical person, you can intercept the packets and reconstruct the data yourself. But ultimately, the reason this is (1) "difficult" is because Flickr is trying to prevent you from doing it. In the future, it may be (2) "impossible" - if Flickr changes its video-system and strongly encrypts its data transfer, it will be impossible to play the video-data in "untrusted" video players (even if you manage to intercept and download it). My recommendation is do not use Flickr - or Youtube - or any other web site - that asks you to sign away the rights to your own content. Host your own photos, videos, and data on your own servers - it is not very difficult to learn how to do. I realize that this sort of runs against the grain of the "web 2.0" movement - but it is the most sustainable way to re-democratize the internet. Nimur (talk) 17:48, 20 August 2010 (UTC)
Amen, Nimur!--el Aprel (facta-facienda) 23:07, 20 August 2010 (UTC)
You say "impossible", but at some point the video must be decrypted in order to be played, at which point can it not be intercepted and recorded unencrypted? (talk) 23:34, 22 August 2010 (UTC).
The video can be decrypted on the graphics card - this task might be performed by a proprietary video-driver; and if the server chooses, it may require a signed/certified/authenticated driver. On July 12th of this year, we had a discussion about Youtube-videos, and I linked to several of the new technologies that Flash is using to make this kind of data-interception prohibitively difficult - in particular, securing and encrypting the video-data through your operating system and all the way to your video-driver. If Adobe Flash video uses hardware-acceleration, and interfaces to a proprietary, binary video driver to perform the decryption, then intercepting the data will be impossible (in the cryptographic sense). This is why it is so critical for digital rights activists to push for open-source alternatives to Flash video - like HTML5 video; and to promote free alternatives instead of restricted binary video drivers; and to discourage web providers from choosing proprietary encryption schemes. If data must be encrypted for transport, it should be relayed with Transport Layer Security to the end-user - not to the proprietary commercial software that has hijacked the user's hardware. Encryption should not be used to deny access to the video data once it is delivered. Nimur (talk) 16:11, 23 August 2010 (UTC)

64 bit[edit]

A have a few questions about 64-bit. Can you install a 32-bit OS on a 64-bit computer? When a program has both 32-bit and 64-bit versions, what is the actual difference between them? Why is 64-bit necessary, is it really impossible to get more than 4 GB of ram on a 32-bit system? (talk) 14:51, 20 August 2010 (UTC)

For both Intel and SPARC then yes, you can install a 32 bit OS on a system running a CPU; I don't know about other architectures. A 64 bit OS allows native 64 bit ints and 64 bit pointers (although a given 64 bit application may not necessarily be compiled that way). Yes, you can get more than 4GB of RAM on a 32-bit Intel system, using Physical Address Extension. -- Finlay McWalterTalk 15:01, 20 August 2010 (UTC)
Right - as Finlay has effectively pointed out, "64-bit computer" is not sufficient to identify the type of computer. Often, (nowadays in 2010), "64-bit" is synonymous with "x86_64", the 64-bit architecture used by Intel and AMD. For this specific type of system, 64-bit hardware is backwards compatible with all 32-bit software (though 32-bit software does not take full advantage of the new capabilities).
64-bit computers actually physically connect to more memory by providing more physical wires (and a set of instructions to directly load and store data using those wires). PAE, a specific way to extend 32-bit Intel computers' address space, is sort of like a compromise - PAE adds physically connected RAM, up to 36-bits worth. And it provides a way for a 32-bit system to compute and use 36-bit addresses, increasing the total number of memory locations that can be reached directly.
As far as "impossible" to extend beyond those limits: well, there is a fundamental rule in computer science that can be roughly summarized: all computers can emulate any behavior that any other computers can do. So, it is definitely possible to load an arbitrary quantity of RAM on a 32-bit platform (or even a 4-bit computer). But it won't be very fast! In a sense, a "hard disk drive" is a serially-accessible memory unit that can serially store "arbitrarily large" quantities of data - but it is not RAM in the literal sense, for exactly this reason. Though, technology exists to "emulate" random addressing on any type of storage-medium; and it is very common to pretend that the disk is RAM!. Nowadays, you can even buy RDMA servers, so you aren't limited by disk scan-speeds, and can add "arbitrarily large" quantities of network-attached RAM that is faster than disk access. But you still have to transfer the data from somewhere to the CPU; and the CPU needs to calculate where that data resides and how to get to it, (and handle the message-passing necessary to execute the transfers, and so on). Since such "emulation" means that there is not a direct connection between the CPU and any "random" address, it is slow to load data from these extended address spaces - and usually, computer designers don't like to spend a lot of time "emulating" basic operations like finding an address in memory. Most common operating systems will not permit you to address beyond the physical memory limitations of the CPU, because they know this is a dumb idea and will slow your computer programs to a grinding halt - but for some very specialized purposes, you can find extremely large-memory operating-systems that work on 32-bit CPUs. Nimur (talk) 17:38, 20 August 2010 (UTC)
One benefit of the x86_64 was that it gave them the excuse to change some things. The 32-bit x86 was notoriously register-starved (it had very few places to store intermediate values). It would've been easy to add registers to 32-bit machines, but it would've required a large, coordinated change for compilers to make use of them. The 64-bit transition provided the large, coordinated change, so programs compiled for 64-bit x86 can make use to the additional registers. Paul (Stansifer) 19:03, 23 August 2010 (UTC)
(By "them", I think Paul Stansifer means "Intel and Hewlett Packard's compiler designers; and by proxy, the free software Open64 and eventually the gcc projects that track the progress of the commercial compilers." Nimur (talk) 20:38, 23 August 2010 (UTC) )

Button on taskbar disappeared, the sequel[edit]

I forgot to ask about a way to videotape this. The computer has Firefox and is at a library.

This refers back to this question and this sequel.

This may not help anyone diagnose WHY the problem is happening, but today, when an ad was slow coming up, I switched to another window, and the button for the window I had been on disappeared. I was able to return to the window where I had been by clicking on the button for the window that I had gone to, and magically the button for the window whose button was gone appeared on the right, though it had started out on the left.

Last night, I had three buttons. I tried to switch to one of the buttons while an ad was very slow to come up, and then the button wasn't there, and Alt-Tab wouldn't make it come back. A few minutes earlier, one button disappeared, but by clicking on one of the buttons twice, the window came back and then the button did too.

On another occasion I had just two buttons and lost one.

I saved the addresses somewhere (but I don't know where) of the web sites that are particularly problematic today. This being at a library, I doubt they'll put in ad-blocking software. I think one of the addresses I was seeing at the bottom of the screen when an ad was slow to come up was · talk · contributions · 18:04, 20 August 2010 (UTC)

Without knowing the operating system of the computer and ALL of the software running on the computer, this cannot be diagnosed as a problem. It could be the design of whatever is running. Further, it would help if you used language that is common for others. You appear to be referring to the taskbar. When you say "button", most people will assume you are referring to a button somewhere on the screen, not a task on the taskbar. When you say that a button disappeared, you appear to mean that a task disappeared from the taskbar. Not all taskbars are the same. Some have grouping. When multiple tasks group together, they are shown as a single task. Others have hiding. Based on some rules, tasks that aren't being used will be hidden from the taskbar. So, without knowing exactly which taskbar you are using, it is hard to say that this is not how the taskbar is designed to operate. -- kainaw 18:46, 20 August 2010 (UTC)
Just be glad I figured out I could call it a taskbar. I used to refer to "the rectangles at the bottom of the screen". One day I listened to those who want me to Google for information and found the term "taskbar" and the term "button". It looks almost exactly like Taskbar#Screenshots but without the "e" and other symbols. When I say "button" I am referring to the blue rectangles, and they generally have a web site name, or sometimes just "Mozilla Firefox". One today said "Compose mail". There is no grouping taking place. These buttons are not supposed to disappear. And the tasks are not stopping. They are just hiding (and not because software was written for them to hide). This has only been going on for a couple of weeks.
Screenshots ... that gives me an idea. I don't know that anyone would videotape me working, but I could do a screenshot. Although I don't really know howVchimpanzee · talk · contributions · 19:18, 20 August 2010 (UTC)
VChimpanzee, based on the contents of your nearly weekly questions, you seem to be having extreme difficulty with basic operation of these computers. Either something is seriously faulty with the equipment, and you should report it to the owner/operator of the library-computers; or you should seriously consider an introductory class in operation of web-browsers. Check with your library to see if they offer a course in basic internet and computer use. If you are honestly unfamiliar with the basic terminology and operation, you might benefit a lot from a structured training course. We have a policy of assuming that you are posting your questions in good faith, but your descriptions and questions are really becoming quite inane - in this particular instance, it is not even clear what you are asking. There is a limit to how long these rants will be tolerated. Nimur (talk) 20:13, 20 August 2010 (UTC)
I am asking why these buttons are disappearing. I went to the trouble of learning what the terms were and even that wasn't enough for some people. I am not ranting. I am asking valid questions.Vchimpanzee · talk · contributions · 20:22, 20 August 2010 (UTC)
You will get better answers if your posts are formulated as questions and concisely summarize your problem. There is definite lack of questions, or even "?" punctuation in your posts. Nimur (talk) 21:28, 20 August 2010 (UTC)
You have been given two answers, both of which you appear to refuse to consider:
  1. It is by design. The library has some modified taskbar program that purposely hides things. Without knowing what modifications are installed, we cannot make guesses about it.
  2. There is a virus or malware on the computer. Without knowing specifically what is infecting the computer, we cannot make guesses about it.
Until you can definitely show that the library has not modified the operating system and that there is no infection on the computer, we cannot go any further. -- kainaw 15:26, 21 August 2010 (UTC)
If you're using Microsoft Windows 7; right-click the Windows button, and select Properties. Choose yhe Taskbar tab, and select Never Combine option in the Taskbar buttons: drop-down menu. This will stop multiple simultaneous windows of the same application from being grouped into the same task on the Taskbar. But be warned that depending on how many applications and how many windows of each you have open at the same time, this could clutter up your taskbar very quickly; if your taskbar overflows, excess tasks will be automatically hidden in a menu accessible by clicking the double-right-arrow-bracket button which will appear on the taskbar just before the system tray. You should also consider increasing the size of your taskbar to double-height or triple-height.
I agree with [User:Nimur|Nimur] though, in that you benefit greatly from structured training in basic computer and internet usage. As for going "to the trouble of learning what the terms were", IMHO, if you consider that troublesome, no offence but you probably shouldn't be operating a computer and/or accessing the Internet. In addition, the wording of your original post is much more closely resembles a rant than a question, and insuufficient details (operating-system, browser-application, etc.) have been provided. Rocketshiporion Sunday 22-August-2010, 12:50pm GMT

────────────────────────────────────────────────────────────────────────────────────────────────────It's not Windows 7. I despise that operating systems taskbar feature. I do go to a library with Windows 7 but I'm pretty sure I can't change properties like that. I have IE8 at home with Vista and while the problem I am describing HAS happened there, and this is recorded in the reference desk archives, it was a somewhat different and, really, less annoying situation because it happened when ... well, I don't know what happened. One window froze and no one was able to give me any clues as to why, but I could continue to do other stuff. As for why it's happening on Firefox, it is not the library doing it. I could suggest they check for malware. It didn't happen today. That's all I know. And it doesn't normally happen.

Here's a summary of what happened Saturday, if it will help anyone figure this out (I wish I had thought of this when I was listing every step in hopes someone would figure out the forward button problem):Vchimpanzee · talk · contributions · 18:38, 25 August 2010 (UTC)

August 21 events
I'm here today because an article in my actual newspaper had information I felt needed to be added to Wikipedia. I provide details hoping they will lead to clues as to what's going on. For example, the Internet is extremely slow at this library today and the buttons have been disappearing right and left. The person here has no idea why. The person in charge of maintaining the computers doesn't know, but he's not here today. I was hoping something I said would give someone a clue. Let me tell you what's happening now. Right now there are no buttons on what Explorer would call the taskbar. A minute ago there were two, both saying "Editing User talk: Nimur". There's no reason why that should have been true. And the screen went blank for a minute, with a blue border, wider at the top, with the Firefox logo, "Editing User talk:Nimur (section)" etc., and the minimize, maximize and Red X. Yesterday this computer was working fine but the person at the circulation desk complained to the appropriate people (who are not here today) that the Internet was slow. I can also tell you that earlier today (it's not true now) there was a delay between my typing a letter and the letter appearing on the screen.Vchimpanzee · talk · contributions · 17:24, 21 August 2010 (UTC)
The Internet seems faster now. No buttons, though.Vchimpanzee · talk · contributions · 17:26, 21 August 2010 (UTC)
The button mysteriously reappeared, and when I clicked on it the other web site I was on came up, with its own button. I'm sorry if you have no idea what this is, but I provided all the details I could. If there's no point in adding them to the reference desk then I guess I won't, but there must be someone who knows what this is.Vchimpanzee · talk · contributions · 17:38, 21 August 2010 (UTC)
I clicked on one of the buttons and got a third web site, which I don't need now because it was going to serve as the notepad, and I already have that. I should mention that I clicked on the Firefox logo several times because it was slow to do anything. If you know of a way I can record such information, like that list of steps, other than on the reference desk, I'd like to hear it.Vchimpanzee · talk · contributions · 17:56, 21 August 2010 (UTC)
I finished the newspapers. No one is going to put ad-blocking software on this library's computers. This one is the one those who are not students normally use. One ad was slow to come up ( I believe appeared at the bottom of the screen) and the button disappeared. Then somehow it came back but I didn't see when.Vchimpanzee · talk · contributions · 18:06, 21 August 2010 (UTC)

Registry access from a different OS[edit]

I have a computer which dual boots into Windows XP Home and Professional; or did before its Home edition died. It is still technically installed but impossible to boot into. What I need to know is, how can I access the registry of Windows XP Home from Windows XP Professional? Thanks. (talk) 21:41, 20 August 2010 (UTC)

Assuming you can actually see the Windows XP Home installation files, you can load the registry hive. To do this you need to run the registry editor (regedit.exe) and click HKEY_LOCAL_MACHINE (because I assume that's what you want to edit given the problem with it not actually booting). Then from the file menu select "Load Hive" and navigate to the Windows\SYSTEM32\Config folder of your Windows XP Home machine (You have to click the key other Load Hive will be greyed out). Select the file you want to open depending on where in the registry you want to edit (SOFTWARE or SYSTEM probably?) and if I remember correctly it'll then ask you for a name to call this, you can call it anything you like, it's just for your reference and it'll appear mounted from that point. If you want to open another key just repeat the process. Do your editing and unload the Hive pretty the same way. Hope this helps!  ZX81  talk 22:10, 20 August 2010 (UTC)
Microsoft link about it is here (although they don't go into any great detail!)  ZX81  talk 22:12, 20 August 2010 (UTC)
There's a linux program that allows this too, although the name escapes me right now. Let me know if that would be helpful and I can find out the name for you. Shadowjams (talk) 02:58, 21 August 2010 (UTC)
chntpw (what, no article?) with commandline parameter -e. -- (talk) 20:02, 23 August 2010 (UTC)

Program to compare drives/folders[edit]

Let's say that I cloned a hard drive onto another drive, but I think something may have gone wrong, as the total space used, and total number of files are different now. Anyone know of a (free) program that can compare the two drives? Sort of like a duplicate file folder, only opposite (if that makes sense). Thanks. - (talk) 21:52, 20 August 2010 (UTC)

FastCopy can, just select the two drives and click "Listing" and it will output a list of any differences. It can copy any missed files so that the cloned drive contents are identical to the original, without having to recopy the entire drive again. ICE Mirror can also do this (talk) 21:56, 20 August 2010 (UTC)